[c-riq]

That is true, the location proof is only for the hardware whose IP is used for submitting the vote request. However if remote desktop provider / cloud provider / VPN / Tor IPs are already blocked by the voting platform. Then it would require significant effort to acquire hardware in the target geographic region and equip it with a residential IP. Generally the whole setup only makes sense if IP's (or IP ranges) can only vote once per poll. Then large scale manipulations should become impractical.

[nine_k]

You are describing an ideal use case for a botnet of compromised home computers. Should command a much higher premium than sending spam.

[DeepYogurt]

For a motivated attacker its not that hard to add a few thousand raspberry pis to a residential internet network in most countries. Its really a quite practical attack when the stakes are governmental control.

[myself248]

Or just compromise an entire ISP full of routers...

[j16sdiz]

or just sell ISP the routers you made.

[kvdveer]

No need for lots compromised devices. Just a single device (probably doesn't need to be compromised) in IPv4 behind carrier grade NAT is typically enough to vary your IP, or plausibly reuse an IP.